Gasoline power tools such as chain saws or mowers have been provided with a stopping switch for stopping the ignition of its engine but is not provided with anything corresponding to an ignition key mechanism or door locking mechanism as in an automobile or motor cycle and, therefore, such relatively portable machines can be used by anyone, simply by operating the internal combustion engine comprising the prime mover.
Therefore, even a child may mistakenly such tools, causing an accident or injury to himself or others. A thief can also easily use the tool resulting in a prolification in the loss of such tools.